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排序方式: 共有1209条查询结果,搜索用时 31 毫秒
71.
本文提出了一种烟道气净化的新型净化装置,并对其进行了实验研究,分析了除尘机理.该装置采用三相分离元件,除雾、除尘效率高,同时还能减少有害气体的排放,是一种很有开发前景的新型湿式除尘技术 相似文献
72.
杜惠平 《重庆邮电学院学报(自然科学版)》1998,10(4):15-17
圆环天线是一类应用较为广泛的重要的线天线形式。然而,因为其数学处理略为复杂,一般教科书中较少涉及。而在作者所见到的两本教科书中则存在着同样的错误,通过对有关问题的讨论,修正了文献听错误。 相似文献
73.
J. M. Aguirregabiria Ll. Bel J. Martín A. Molina E. Ruiz 《General Relativity and Gravitation》2001,33(10):1809-1837
To compare two space-times on large domains, and in particular the global structure of their manifolds, requires using identical frames of reference and associated coordinate conditions. In this paper we use and compare two classes of time-like congruences and corresponding adapted coordinates: the harmonic and quo-harmonic classes. Besides the intrinsic definition and some of their intrinsic properties and differences we consider with some detail their differences at the level of the linearized approximation of the field equations. The hard part of this paper is an explicit and general determination of the harmonic and quo-harmonic coordinates adapted to the stationary character of three well-know metrics, Schwarzschild's, Curzon's and Kerr's, to order five of their asymptotic expansions. It also contains some relevant remarks on such problems as defining the multipoles of vacuum solutions or matching interior and exterior solutions. 相似文献
74.
This paper deals with Lagrangian bundles which are symplectic torus bundles that occur in integrable Hamiltonian systems.
We review the theory of obstructions to triviality, in particular monodromy, as well as the ensuing classification problems
which involve the Chern and Lagrange class. Our approach, which uses simple ideas from differential geometry and algebraic
topology, reveals the fundamental role of the integer affine structure on the base space of these bundles. We provide a geometric
proof of the classification of Lagrangian bundles with fixed integer affine structure by their Lagrange class.
相似文献
75.
SOME REMARKS ON HOLOMORPHIC FUNCTIONS AND TAYLOR SERIES IN Cn 总被引:1,自引:1,他引:0
余家荣 《数学物理学报(B辑英文版)》2008,28(4)
Some previous results on convergence of Taylor series in Cn [3] are improved by indicating outside the domain of convergence the points where the series diverges and simplifying some proofs. These results contain the Cauchy-Hadamard theorem in C. Some Cauchy integral formulas of a holomorphic function on a closed ball in Cn are constructed and the Taylor series expansion is deduced. 相似文献
76.
One of the most well-known situations in which nonlinear effects must be taken into account to obtain realistic results is
the rotating beam problem. This problem has been extensively studied in the literature and has even become a benchmark problem
for the validation of nonlinear formulations. Among other approaches, the substructuring technique was proven to be a valid
strategy to account for this problem. Later, the similarities between the absolute nodal coordinate formulation and the substructuring
technique were demonstrated. At the same time, it was found the existence of a critical angular velocity, beyond which the
system becomes unstable that was dependent on the number of substructures. Since the dependence of the critical velocity was
not so far clear, this paper tries to shed some light on it. Moreover, previous studies were focused on a constant angular
velocity analysis where the effects of Coriolis forces were neglected. In this paper, the influence of the Coriolis force
term is not neglected. The influence of the reference conditions of the element frame are also investigated in this paper. 相似文献
77.
陈希明 《重庆邮电学院学报(自然科学版)》1998,10(1):73-75
作者在该文中从世界空间的四维坐标和四维波矢量出发,证明了电磁波的相位不变性。此方法数学形式简洁,物理意义突出。 相似文献
78.
Petr Hájek 《Journal of Mathematical Analysis and Applications》2008,338(2):1131-1139
Let X be a separable Banach space with a Schauder basis, admitting a continuous bump which depends locally on finitely many coordinates. Then X admits also a C∞-smooth bump which depends locally on finitely many coordinates. 相似文献
79.
Efficient Evaluation of the Elastic Forces and the Jacobian in the Absolute Nodal Coordinate Formulation 总被引:1,自引:0,他引:1
This paper develops a new procedure for evaluating the elastic forces, the elastic energy and the jacobian of the elastic
forces in the absolute nodal coordinate formulation. For this procedure, it is fundamental to use some invariant sparse matrices
that are integrated in advance and have the property of transforming the evaluation of the elastic forces in a matrix multiplication
process. The use of the invariant matrices avoids the integration over the volume of the element for every evaluation of the
elastic forces. Great advantages can be achieved from these invariant matrices when evaluating the elastic energy and calculating
the jacobian of the elastic forces as well. The exact expression of the jacobian of the differential system of equations of
motion is obtained, and some advantages of using the absolute nodal coordinate formulation are pointed out. Numerical results
show that there is important time saving as a result of the use of the invariant matrices. 相似文献
80.